Changes in temperature and rainfall will increasingly threaten agriculture in the region, according an early release of some findings of the USAID-funded “Mekong Adaptation and Resilience to Climate Change.”

“The Greater Mekong Subregion is one of the most vulnerable regions in the world with respect to climate change and its effects on agriculture production systems, including fisheries,” Ulrich Apel, an environment researcher for the Global Environment Facility, said.

Added to the potential threats of climate change are the many dams planned in Mekong countries, experts said.

The impact for 60 million people living on the Mekong River “could be disastrous,” Aviva Imhof, campaigns director for the US-based International Rivers, told VOA Khmer. “By blocking the transport of sediment, the dams will contribute to even greater erosion in the fertile Mekong Delta, which is already threatened by increasing saltwater intrusion as a result of rising sea levels.”

The combined threats of dams and climate change could severely damage fish stocks, impacting food security for many people living along the river, particularly Cambodians, Zachary Dubel, a researcher at the Stimson Center, told VOA Khmer.

“The Mekong River is the world’s most productive freshwater fishery, but it is being stressed by overfishing and fast population growth that looks to increase significantly over the coming decades,” he said.

Cambodia, Laos, Thailand and Vietnam rely heavily on the Mekong River, and these countries spend millions of dollars annually to protect areas of the river. But experts warn they most find common solutions to the impending problems.

The Global Environment Facility committed $92 million for a four-year project that ends in 2014, aiming to mitigate the impacts of climate change, conserve biodiversity in the region and fight land degradation, Apel said.

But it is up to the Mekong countries themselves to “work together to tackle these issues,” he said.

Climate change is a “transboundary” problem that requires a transboundary solution, Dubel said. The Mekong River must be viewed similarly, he said. “As a river that runs through six countries and provides a great number of environmental services to millions of people, it is vital that the river be managed collectively,” he said. That includes information sharing, as well as coordinated policies, he said.

Currently, that is not happening, and a number of dam projects are being developed by various companies with insufficient coordination, he said.

“Lack of cooperation on mainstream hydropower in the present has already created tension between upstream and downstream countries that threatens regional relations at a time when multilateral cooperation on issues, such as adaptation to climate change, is extremely important,” he said. “Furthermore, those dams that have been built already require increased coordination between themselves in order to effectively manage flows between them, particularly in light of the increased rainfall the region will receive in the future and threat of floods.”

Long-range and comprehensive impact assessments are needed before such dams are built, he said.

International River’s Aviva urged Mekong governments to reconsider the dams. Countries of the region need to make sure they are taking on “no-regrets” measures to ensure their economies are “as climate resilient as possible,” she said.

“The proposed dams for the Mekong region are also not being designed with climate change in mind,” she said, “with the result that some dams may be uneconomic, as there won’t be enough water to generate power, and other dams may be risky, as they will not be built to withstand greater floods and extreme weather events predicted by climate change.”

With 11 mainstream dams and scores of tributary dams planned, the impacts of climate change could be greatly increased, she said.

The Mekong adaptation report, whose full results will be issued March 29, found “shocking results,” report author Jeremy Carew-Reid said in a statement. “We’ve found that this region is going to experience climate extremes in temperature and rainfall beyond anything that we expected.”